String Theory

A Wikibookian believes this page should be split into smaller pages with a narrower subtopic.

You can help by splitting this big page into smaller ones. Please make sure to follow the naming policy. Dividing books into smaller sections can provide more focus and allow each one to do one thing well, which benefits everyone.

Greek letters from the middle of the alphabet (μ,ν,...){\displaystyle (\mu ,\nu ,...)} denote coordinates in spacetime. Roman letters taken from the beginning of the alphabet (a,b,...){\displaystyle (a,b,...)} denote coordinates on the worldsheet.

The metric is denoted gμν{\displaystyle g_{\mu \nu }}. In the case where there is a metric of spacetime and a metric of the worldsheet, the worldsheet metric is denoted hab{\displaystyle h_{ab}}

A lower-case d{\displaystyle d} is the number of dimensions. An upper-class D{\displaystyle D} represents the number of spacial dimensions.